Rilevata connessione cablata Ubuntu 14.04 ma nessun accesso a Internet

Non ho accesso a Internet con connessione cablata su Ubuntu 14.04 anche se viene rilevato, il mio computer è collegato allo stesso router.

$ ifconfig
eth0      Link encap:Ethernet  HWaddr 4c:72:b9:7e:b5:61  
          inet addr:192.168.1.2  Bcast:192.168.1.255  Mask:255.255.255.0
          inet6 addr: fe80::4e72:b9ff:fe7e:b561/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:93 errors:0 dropped:0 overruns:0 frame:0
          TX packets:705 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:18292 (18.2 KB)  TX bytes:76277 (76.2 KB)
          Interrupt:17 

lo        Link encap:Local Loopback  
          inet addr:127.0.0.1  Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:65536  Metric:1
          RX packets:701 errors:0 dropped:0 overruns:0 frame:0
          TX packets:701 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:54442 (54.4 KB)  TX bytes:54442 (54.4 KB)

wlan0     Link encap:Ethernet  HWaddr 08:3e:8e:5f:56:1e  
          UP BROADCAST MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)

Buona. Quindi non hai nameserver DNS. Aggiungi queste due righe a /etc/resolv.conf :

  nameserver 8.8.8.8
  nameserver 8.8.4.4

e dovrebbe funzionare.